In what seems to be a widespread hack, multiple investors on Bengaluru-based Bitcoin exchange Unocoin have reported unauthorised transfers of the virtual currency from their accounts. Users have reported unauthorised transfers of 0.25 BTC from their Unocoin accounts.

The exchange has accepted the responsibility of the situation and has assured customers about refunds in case of the lost Bitcoins.

The accounts lost Bitcoins Sunday evening. “Suddenly, last evening I received two emails notifying me of transactions worth 0.25 BTC from my account. The first transactions happened at 5:42pm and the second transaction at 6:04pm. I had not authorised these transactions,” said Mumbai-based virtual currency investor Durgesh Pandey, who has been using Unocoin since last December.

All the hacked transactions were of the value 0.25 BTC and several users said that their transfers were in the pending state.

Responding to these messages, Unocoin tweeted Sunday night saying, “Apart from few txns of 0.2505 BTC each, our server has stopped the txns & are in pending state. It will be cancelled/refunded as appropriate.”

Sir,we are taking the responsibility for your lost coins.Do not panic we are taking care of your BTC AND ACCOUNT as well. https://t.co/ACppeEUdSM

Unocoin also said in a tweet that the incident is not a server compromise from initial looks of it. As a precautionary measure, the company has disabled user logins and said that the service will be up by the end of Monday.

“Only seven to eight transactions went through and before the rest of the transactions could go through, our server detected a pattern and halted the rest of the transactions. It was not a server side hack and we will be reverting back all the transactions in the next couple of hours,” Sathvik Vishwanath, CEO and co-founder of Unocoin told FactorDaily Monday morning.

Bitcoin has been on a bull run and recently crossed the $3,000 mark reaching an all time high price of $3,360.87 and on Saturday the cryptocurrency crossed $50 billion in market capitalisation. After the November 8 demonetization announcement, Bitcoin had gained popularity in India and saw a rise in transaction volumes.

Bitcoin’s market price crossed $3000 mark reaching all time high.

This sudden rise in price and popularity of Bitcoin has made it a prime target for hackers. Also the anonymity behind cryptocurrency transactions makes it easier for hackers to steal them without leaving much of a trace.